With a second fish farm planned for Loch Long and the planning application submitted by Loch Long Salmon Ltd. (LLS) to Loch Lomond and the Trossachs National Park in October 2021 (with a closing date for representations/objections of 5 December, 2021), we should all be concerned at the rapid growth of proposed fish farms in Loch Long, the River Clyde and Scotland as a whole.
The Technology
Unlike conventional open net fish farms, the Loch Long proposal at Beinn Reithe (just north of Glenmallan on the west side of the loch) will use a relatively new technology in semi-closed fish farm systems (SCCS) manufactured by FiiZK, Norway. LLS will be using an impermeable but flexible outer skirt surrounding an inner traditional net cage and a waste solids collection system allowing the sludge to be pumped ashore, dewatered and the resulting product made available for further use. Clean water is drawn from depth and oxygenated, thereby minimising or eliminating sealice infestation. The farm will comprise of 4 circular enclosures, each of 50m in diameter as well as a 50m square shaped semi-closed harvesting facility, workboat moorings, floating pontoon, floating feed and services to the marine farm as well as shore-based facilities for full description see Planning Application ref. 2021/0357/DET at https://eplanning.lochlomond-trossachs.org/OnlinePlanning.
The technology has been trialled in British Colombia (BC), by Cermaq Canada, however in October 2021 the company abandoned the trial with Dr. Peter MacKenzie, director of fish health at Cermaq stating that “SCCS is immature technology under development, therefore it is not surprising when you are trialing new technology you will run into challenges. This was our first attempt to grow fish of varying sizes in a semi closed environment and unfortunately, due to water quality issues, fish performance was affected and resulted in fish mortality.”
Local Canadian conservation group Clayoquot Action who had been observing the trial since October 2020 noted fish die-offs at the facility and cited possible reasons for the premature ending of the trial in a recent article. This included the location being packed with jellyfish which may have clogged the system (as the fish need freshly oxygenated water to breathe) as well as spreading Tenacibaculum maritimum, which causes mouth rot. The British Colombia federal government commissioned a study of closed containment technologies and concluded that “floating closed containment requires 2-5 years of further review”.
Analysis of Loch Long Salmon’s Planning Application (2021/0357/DET)
Site/Location/Tourism/Shipping
Chapter 3.2 states that several Loch Long locations were considered, however as the semi-closed technology requires a sheltered environment, Bienne Reithe was selected. The application also mentions that the site avoids conservation areas, however as the location is in a National Park, should the whole area not be considered a conservation area? Loch Long landscape designation (LLD) on the other side of loch 215m east of site is surely a visual impact issue?
Considering the site boundary as shown at Chapter 4 Fig. 4.1, the positioning of the marine component takes up a prominent and commanding position in the loch (this is to take advantage of the 50 metre depth), what effect would this have on navigation of the loch in particular Waverley cruises to the top of the loch as well as other leisure shipping?
> It could be considered that the installation represents a potential obstruction and is visually much more prominent.
Sealice
Chapter 3.4.4.1 LLS states “With no anticipated sea lice outbreaks, chemical treatments for sea lice, usually applied indirectly to the fish via the pen water or directly in the feed, are unlikely to be required. This brings benefits in terms of fish welfare, as well as reduced impacts on water quality and benthic ecology..”, however at Chapter 10.5.2.1 it states “should sea lice be recorded within any of the enclosures contingency measures including the deployment of cleaner fish, the use of well boat and bath treatments, including the use of hydrogen peroxide, and mechanical treatment may be used”.
> It is claimed hydrogen peroxide is easily broken down, diluted and decomposed with no harmful by-products in the environment, however this is not the experience reported from study work in Norway, therefore we disagree with this statement over lack of harm to the surrounding marine environment.
Waste collection
The facility is serviced from shore with onshore handling of feed so no feed barge is required. However, only a proportion of the waste is collected and pumped ashore. The LLS website states “We will remove more than 80% of these waste products, therefore reducing the benthic impact per kg of salmon produced.”.
> As waste collection efficiency could be compromised by turbulence within the pen affecting settlement of waste particles or simply swept out with excess water through ports in the outer bag, how will the remaining waste affect the environment?
Chapter 4.3.1.1 The level of dewatering (95% removal) of the faeces slurry is likely to be unattainable with the equipment proposed. At this moisture content the product would in all probability be a solid. This observation is confirmed somewhat when it is later stated the slurry is “pumped” into a road tanker.
LLS predicts that 85% faeces and 100% uneaten food will be collected. The waste is pumped from the sump and transported back to land for treatment via a low-pressure surface pipe which forms part of the floating umbilical. Wastewater system involves screening, coagulation and dissolved air flotation of solids. Dewatering is stated to be at least 95% efficient with all water removed from waste stream and pumped back into the loch.
> This efficiency appears to be highly unlikely considering the product would be mostly a solid residue. If this was the case and later the slurry is pumped into the tanker for off-site transport (which points to a much greater water content than 5%), this could create a huge odour issue unless expensive pressure filtration and odour control was installed.
Maximum Biomas
Chapter 4.3.5:
> Max biomass mentioned is 570 tonnes, whereas 4000 tonnes is quoted widely elsewhere in the chapters.
Stocking rate
Chapter 4.3.5.2:
> Stocking rate quoted is 5% fish / 95% water which is twice as great as the highest acceptable open cage stocking density. This raises major husbandry and general animal health and welfare issues as well as potentially promoting disease.
Chemical treatments
> LLS state that chemical treatments are unlikely to be required, however this was not the case in the recent British Colombia experience of a viral outbreak.
Hydrological
Given the location of the fish farm at Beinn Reithe (near the head of Loch Long), one would expect the waters there to be highly stratified at certain times of the year and under different meteorological conditions with lower layers being more saline than upper surface condition, especially with high freshwater runoff from the Loch Long upper catchment.
> Salinity and temperature control could be a real problem. How will LLS address this aspect?
Water environment
Given the contribution to this very enclosed head of the loch brackish water environment of nitrogen and phosphorus nutrients (including ammonia), soluble pollutant vectors not contained within the development could pose a major risk of eutrophication and resultant phytotoxic blooms.
> Major risk of eutrophication and resultant phytotoxic blooms. How will LLS. address this?
Growth period
It appears that the proposal is to rear post smolts up to a size under 1kg. This begs the question as to where these fish are transported to, in order to finish their growth period to marketable size of 4-5 kg. The LLS website quotes “Post-smolt are fish that are grown in the farm for a period of months from when the fish are delivered to the farm as 80g to 100g salmon smolt and reared until the stock has an average weight of 600g to 1000g. In this farming system, the post-smolt would be transferred to an existing conventional open net salmon farm and grown to full harvest size at this new location. Environmental benefits are retained in the local area and research has shown that the benefits to fish health and welfare continue to benefit the stock started in a semi-closed farm with less sea lice treatments, better survival and faster growth all demonstrated. When the stock reach transfer size, they would be transferred to the finishing farm in a well boat. The farm would be left fallow for a period of weeks prior to re-stocking.”.
> It would appear that greater capacity would be required at an “existing conventional open net salmon farm” to accommodate the fish from Beinn Reithe. Is this therefore not negating the whole concept of the semi-closed system, whereby an open net facility would still be required for the Loch Long stock?
Sustainability
Feed source
As there appears to be no mention in the planning documents regarding source of feed supply, one could therefore conclude that it is not from an environmentally sustainable source and therefore may not meet the UN SDG goal.
> Environmentally sustainable feed source?
Marine Mammals – Seals
Chapter 10 states “As discussed, in Chapter 9: Marine Mammals, seals are the primary predator of marine salmon farms, and such predator events have the potential to lead to net breaches that result in escape events occurring. Therefore, the risk of an escape event occurring is greatly increased where an abundant population is present. No designated seal haul outs are located within Loch Long, with the closest site located on Ailsa Craig, approximately 80 km away. In addition, a 2017 field study carried out by Sea Mammal Research Unit (SMRU) and Marine Scotland, categorised Loch Long as being of low density for harbour seal and absent of grey seal. As a result, the risk of predation related escape event is considered to be very low.”
> It may be the case that Ailsa Craig is the nearest Marine Scotland designated site, however Loch Long has a seal population especially at Ravenrock Lighthouse, Ardentinny.
Chapter 11.5.5
Statements on benthic depositional modelling
“NewDEPOMOD modelling based on a conservative estimate of the anticipated recapture rates (100% waste feed recapture and 85% faeces recapture), indicated that waste released from ports in the side and bottom of the cages at a biomass of 3452T, would consistently pass SEPA environmental quality standards (EQS).”
> Unlikely to be achieved. Computational flow dynamic modelling, simply applying the science of fluid flow may have been used to describe behaviour of water flow through the pen and out into the loch. Details are not available and appear reserved for the separate SEPA CAR licence application.
> Report mentions biomass of 3452 tonnes but the question is, where has this figure come from? This figure is repeated on the next page 11-10.
Chapter 11.4.1.2 Discusses IEFs (Important Ecological Features) in accordance with CIEEM (Chartered Institute of Ecology and Environmental Management) guidance to assess biodiversity and importance of species observed.
> Departure from NatureScot assessment basis and PMFs (Protected Marine Features).
Chapter 11.6.1.2 states dewatering of collected solids at least 95% efficient.
> Unlikely if this is achievable with the equipment proposed and especially as the ‘slurry’ will be pumped into a road tanker to be taken offsite.
Fallow Period
Chapter 11.6.2.2 A two to four week fallow period is proposed.
> Much shorter fallow period than usually practiced at open cage sites, therefore appears to be too short for effective remediation on the seabed.
Hydrology and Soils
Chapter 13.4.7 “Locational Guidelines published by Marine Scotland Science that classify waterbodies on the basis of calculated indices to estimate nutrient enhancement and benthic impacts, classify Loch Long as ‘Category 3’. This indicates an area of low sensitivity to fish farming development and where the potential of nutrient enhancement and benthic impacts are likely to be acceptable.”
> Needs to be looked at more closely as one might expect there to be a risk of eutrophication at the loch head with the risk of algal blooms.
Marine Water Quality
Chapter 14.3.7 The current profile is similar throughout the water column down to over 50 metres depth to seabed at 0.03 -0.04 metres/sec. This is low by comparison with open cage fish farming sites especially in outer reaches of lochs and more exposed sites, but does have implications should the figure of 85% retention and collection of solid waste not be achieved and much more solid waste is discharged.
> Implications should the figure of 85% retention and collection of solid waste not be achieved and much more solid waste is discharged.
14.4 “The Development is situated within the Loch Long (North) coastal water body which the Water Framework Directive (WFD) classification scheme identifies as having “Good” overall status and “Good” overall ecological status. Furthermore, in 2018, the Dissolved Inorganic Nitrogen (DIN) status of the Loch Long (North) water body was classified as “High”, which indicates that the water body has conditions that are associated with no, or very low, human pressure. As defined in Section 14.3.8.1, Loch Long is therefore considered a ‘High’ sensitivity receptor given that it is of high environmental value with no, or very low, human pressure currently…”
> It would appear what the promoters are trying to say is that the water quality is so good that a large input of nitrogen from this fish farm will be assimilated (or in other words diluted) without risk of such a nutrient load promoting undesirable algal or planktonic growth. This would appear to be an assumption especially as it is highly likely that elevated water temperature during summer months will also act as a driver (Photosynthesis driving productivity of plant like phytoplankton). However, they do state that modelling has been done in connection with dispersion of nitrogen and phosphorus. This aspect needs further investigation.
14.7 “..the Development is unlikely to make a significant contribution to nutrient enhancement or to the likelihood of harmful algal blooms and thus, no significant effects are predicted to occur.”
> We do not concur with this statement. The risk cannot be discharged so easily for what is a huge aquaculture project in a highly confined marine location.
Chapter 16 Noise/Light Pollution
> There appears to be too much complacency related to noise/light pollution and relying on background measurement. Considering the development is a 24 hour operation, sound travels very easily across water and often complaints are entirely subjective but very real to those raising the complaint. There appears to be no mention of light pollution from the onshore facilities and any underwater lighting employed to promote growth.
Conclusion
Loch Long Salmon have produced a very slick public relations campaign for local consumption and as to be expected, an extensive planning application. However, what they are proposing is very much new and untried technology. The recent abandonment of the trial in Canada should be a warning to Scotland that the technology is not yet fit for purpose. As we have highlighted in this article, there are a number of areas which need further investigation and questions need to be answered. This is a huge aquaculture project in a highly confined marine location. Should it not function as described (and there is a distinct possibility here), there is a very great risk of a disaster in Loch Long.
HAVE YOUR SAY
You can make representations (closing date 5 December, 2021) related to the planning application as follows:
Online – https://eplanning.lochlomond-trossachs.org/OnlinePlanning/ (enter Ref. 2021/0357/DET). You can add your objection via the “Make a comment” button.
Email – planning@lochlomond-trossachs.org (Ref. 2021/0357/DET)
Post – Post to: Loch Lomond and the Trossachs National Park, Carrochan, Carrochan Road, Balloch, G83 8EG. (Ref. 2021/0357/DET)
Related links:
- 2021/0357/DET Planning Application – Closes 5th December
- Tech Flaws halts Vancouver Island semi-closed fish farm trial
- FiiZK – Semi-closed cage manufacturer
- Loch Long Salmon Ltd
- Community engagement by Loch Long Salmon – Virtual exhibition
- Cermaq’s Semi-Closed Containment System – What is it and what does it do? Quick Facts and Frequently Asked Questions (FAQs)
